Subprocess call in Python interpreter results in memory corruption

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15

With the upcoming feature, it will be possible to easily invoke processes by excluding the Slicer environment.:

  • from c++ (using app->startupEnvironment()), or;
  • from python (using slicer.util.startupEnvironment()

Here are two examples:

Without using the startup environment, this first example fails (as expected):

>>> from subprocess import check_output
>>> check_call(["/usr/bin/python3", "-c", "print('hola')"])
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/home/jcfr/Projects/Slicer-2-build/python-install/lib/python2.7/subprocess.py", line 186, in check_call
    raise CalledProcessError(retcode, cmd)
CalledProcessError: Command '['/usr/bin/python3', '-c', "print('hola')"]' returned non-zero exit status -6

Now, using the sanitized environment, this one succeeds:

>>> from subprocess import check_output
>>> check_output(
  ["/usr/bin/python3", "-c", "print('hola')"], 
  env=slicer.util.startupEnvironment())
'hola\n'